diff --git a/src/DotNetty.Codecs.Http/DotNetty.Codecs.Http.Netstandard.csproj b/src/DotNetty.Codecs.Http/DotNetty.Codecs.Http.Netstandard.csproj
index 2bf91ff8..e0e691f1 100644
--- a/src/DotNetty.Codecs.Http/DotNetty.Codecs.Http.Netstandard.csproj
+++ b/src/DotNetty.Codecs.Http/DotNetty.Codecs.Http.Netstandard.csproj
@@ -16,7 +16,7 @@
     <PackageReference Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWeb2PackageVersion)" />
   </ItemGroup>
   <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.1' ">
-    <PackageReference Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWebPackageVersion)" />
+    <PackageReference Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWeb3PackageVersion)" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/src/DotNetty.Codecs.Http/DotNetty.Codecs.Http.csproj b/src/DotNetty.Codecs.Http/DotNetty.Codecs.Http.csproj
index a1e85d4e..e5636ede 100644
--- a/src/DotNetty.Codecs.Http/DotNetty.Codecs.Http.csproj
+++ b/src/DotNetty.Codecs.Http/DotNetty.Codecs.Http.csproj
@@ -16,7 +16,7 @@
   </PropertyGroup>
   
   <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.1' ">
-    <PackageReference Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWebPackageVersion)" />
+    <PackageReference Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWeb3PackageVersion)" />
   </ItemGroup>
   <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.0' or '$(TargetFramework)' == 'net471' or '$(TargetFramework)' == 'net451' ">
     <PackageReference Include="System.Text.Encodings.Web" Version="$(SystemTextEncodingsWeb2PackageVersion)" />
diff --git a/src/DotNetty.Codecs/DotNetty.Codecs.Netstandard.csproj b/src/DotNetty.Codecs/DotNetty.Codecs.Netstandard.csproj
index 927e5df9..abd702b2 100644
--- a/src/DotNetty.Codecs/DotNetty.Codecs.Netstandard.csproj
+++ b/src/DotNetty.Codecs/DotNetty.Codecs.Netstandard.csproj
@@ -12,12 +12,12 @@
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 
-  <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.1' ">
-    <PackageReference Include="System.Collections.Immutable" Version="$(SystemCollectionsImmutablePackageVersion)" />
-  </ItemGroup>
-  <ItemGroup Condition=" '$(TargetFramework)' != 'netstandard2.1' ">
+  <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.0' ">
     <PackageReference Include="System.Collections.Immutable" Version="$(SystemCollectionsImmutable2PackageVersion)" />
   </ItemGroup>
+  <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.1' ">
+    <PackageReference Include="System.Collections.Immutable" Version="$(SystemCollectionsImmutable3PackageVersion)" />
+  </ItemGroup>
 
   <ItemGroup>
     <ProjectReference Include="..\DotNetty.Transport\DotNetty.Transport.Netstandard.csproj" />
diff --git a/src/DotNetty.Codecs/DotNetty.Codecs.csproj b/src/DotNetty.Codecs/DotNetty.Codecs.csproj
index ee39b1ad..f2d4d8ed 100644
--- a/src/DotNetty.Codecs/DotNetty.Codecs.csproj
+++ b/src/DotNetty.Codecs/DotNetty.Codecs.csproj
@@ -16,7 +16,7 @@
   </PropertyGroup>
 
   <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard2.1' ">
-    <PackageReference Include="System.Collections.Immutable" Version="$(SystemCollectionsImmutablePackageVersion)" />
+    <PackageReference Include="System.Collections.Immutable" Version="$(SystemCollectionsImmutable3PackageVersion)" />
   </ItemGroup>
   <ItemGroup Condition=" '$(TargetFramework)' != 'netstandard2.1' ">
     <PackageReference Include="System.Collections.Immutable" Version="$(SystemCollectionsImmutable2PackageVersion)" />